A 2011 Ranger XLT 4x4 SuperCab automatic.

It has transmission oil cooling in the radiator, and then a separate oil cooler in front, partially obscured by the bumper.

How exactly does this do the cooling?

Does the oil go to the radiator first?

Is the oil heated or cooled in the main radiator? Is heat flowing to or from the coolant?

Any explanation appreciated.

 

The radiator is suppose to cool the transmission, obviously when the radiator is up to temp it is more likely to heat the fluid up tot hat temp then cool it once it goes over. The trans can run hotter than the coolant cant but to a limit. The aux cooler cools the fluid further.

If you are concerned about the trans temp you can install a gauge rather easily on these truck.

 

^^^ what he said. My trans shop that built the trans for my diesel bypassed the radiator cooler and just ran a heavy duty plate cooler in front. For the reason of heating it up. A proper trans should never see temps over 160 unless its towing real heavy or you are flogging the ever living crap outta it. Even then 180 is a redline for mine.

 

Good idea to run it separate from the radiator. I had my Explorer plow truck's radiator go out, the trans mixed with the coolant, not a fun repair job.

Also another reason I hate autos....

 

There is a lot of controversy with running it separate cause people claim the rad gets the trans temp up to normal quicker in the cold. Newer transmissions have a thermal bypass valve on them so it will bypass the cooler to warm up. I still stand by the idea of bypassing the cooler on the radiator to avoid that mixing issue

 

I am running a 24k gvwr aux cooler on my truck with an autometer gauge. Summer temps peak at 150, winter 115. I have hit 180 playing in the snow. My sender is in the pump pressure test port so it is pre cooler temps.

If I was to redo it I would not use the radiator, it just doesn't have a benefit. The computer will limit OD until the trans is up to temp which is a balmy 45 degrees. I think the thermal bypass opens around 100-110.

 

Its an old school pre computer setup that no car maker ever changed.

 

Is that bypass OE, or part of the aftermarket cooler system?

 

Its in the trans

 

So what does this bypass do?

Does it stop flow to the rad. and oil cooler until the ATF gets to 100 -110?

And thanks for the reply.

 

That is my understanding of it, now I cannot find that int he manual any where. So I am not sure where I read that.

 

I was poking around with eyes, fingers, and an IR thermometer to figure out the flow.

The radiator is a cross flow. The hot water from the engine goes to the RHS. The cool water back to the engine exits on the LHS.

The in rad. ATF cooler is on the LHS, i.e. the cooler part of the rad. Hot ATF from the transmission goes in at the top and exits at the bottom.

It then goes to the auxiliary cooler in front of the rad and then return to the transmission.

It seemed that there was warm ATF coming from the transmission even when the ATF temperature was quite a bit less than 100°F, so I'm not sure about this bypass.

But now that I know the flow I'll check that again with a cold engine.

Also I'll try to measure some temperatures at different places after driving hard for a while.